Reverse stitch control knob



w. A. AYREs 2,818,039

REVERSE STITCH CONTROL KNOB Filed Dec'. 30, 1954 mmvrozz. Mme-MAR A Ayah-5 Arr-0R United States REVERSE STITCH CONTROL KNOB Application December 30, 1954, Serial No. 478,775

6 Claims. (Cl. 112--210) This invention relates to a sewing machine and, more particularly, to amechanism for selecting the stitch length of the sewing mechanism in both the forward and reverse directions and for enabling the operator to readily change the direction of the sewing operation without changing the selected stitch length.

In using sewing machines to sew seams in material it is desirable at the end of a seam to take several stitches in the opposite direction of the same length as the seam stitches in order to lock in the seam stitches.

An object of the invention is to provide in a sewing machine an improved and novel mechanism which is operatively connected with the stitch forming mechanism and which can be readily adjusted by the operator of the sewing machine to adjust the stitch forming mechanism to provide for stitches of different selected lengths in both the forward and reverse direction.

Another object of the invention is to provide in a sewatent O ing machine an improved and novel mechanism such that various length stitches can be selected as desired for a different types of sewing operations by adjusting the mechanism and then when desired the operator, by merely moving a direction knob or member of the mechanism against a stop, can obtain the selected stitch length in the opposite direction.

Further and additional objects and advantages not hereinbefore specified will become apparent hereinafter during the detailed description of embodiments of the invention which is to follow.

Referring to the accompanying drawings forming a part of this specification:

Fig. l is a vertical sectional view through the vertical standard of a sewing machine head and in which standard a mechanism embodying the present invention is mounted, said view being taken substantially on line 11 of Fig. 2 looking in the direction of the arrows.

Fig. 2 is a fragmentary front elevational view of the vertical standard of the sewing machine head and shows the direction and stitch length indicating knob or member and the adjusting or stitch length selecting disk of the mechanism.

Fig. 3 is a sectional view taken substantially on line 33 of Fig. 1 looking in the direction of the arrows.

Fig. 4 is a fragmentary top plan view with certain parts omitted showing the cam and the adjusting or stitch length selecting disk of the mechanism, and

Fig. 5 is a view somewhat similar to Fig. 4 but showing a modified form of cam.

The hollow vertical standard of a sewing machine head is indicated at 10 and within said standard internal supporting walls 11 and 12 are provided. The walls 11 and 12 rotatably support a shaft 13 which projects inwardly beyond the wall 11 and outwardly of the wall 12 through an opening 14 in the front of the standard 10. The shaft 13 is operatively connected to the stitch forming and regulating mechanism of the sewing machine, which may be of any preferred and known construction and of the 2,818,e39 Patented Dec. 31, 1957 type providing for different length stitches and for different direction of stitches.

The operative connection between the shaft 13 and the stitch forming and regulating mechanism whereby adjustment of the latter may be obtained by rotation of the shaft 13 different amounts in opposite directions is illustrated as in the form of an adjusting arm 15 secured to the shaft 13 intermediate the walls 11 and 12 and extending downwardly below the bed of the sewing machine where it is connected through members, not shown, with the stitch forming and regulating mechanism, as will be well understood in the art. Preferably the arm 15 is normally spring biased in the forward stitching direction.

The shaft 13 outwardly of the wall 12 is provided with an annular shoulder 16 mounting a collar 17 which bears aginst the outer side of the wall 12 to prevent endwise movement of the shaft 13 in one direction. The shaft 13, as already stated, extends through and beyond the wall 11 and on its extended end has secured to it a collar 18 provided with .1 counterbore in which is a torsional-expansion spring 19, one end of which is anchored to the collar 18 and the other end of which is anchored to the wall 11.

The spring 19 serves the dual functions of maintaining the collar 17 against the wall 12 and of exerting a torque force to rotate the shaft 13 in one direction which, as will later be pointed out, is the forward direction, that is, the direction for forward stitching.

The shaft 13 outwardly of the shoulder 16 is provided with an axially extending keyway 20 in which is mounted the reduced end 21a of a threaded pin 21 with said pin 21 having an outer cam following end 21b that cooperates with a cam later to be referred to. The pin 21 is carried by a sleeve 22 slidable on the shaft 13 but rotatable there with due to the splined connection provided by the groove 20 and the end 21a of the pin.

The shaft 13 outwardly of the sleeve 22 is externally threaded and mounts an adjusting or stitch length selecting disk 23, the circumference of which is knurled to facili tate its turning by the operator. A coil spring 24 surrounds the shaft 13 with one end abutting the wall 12 and the other end abutting the sleeve 22 and acting to maintain said sleeve in engagement with the adjusting disk 23.

Outwardly of the adjusting or stitch length selecting disk 23 a direction control and stitch length indicating knob 25 is fixedly secured to the outer end of the shaft and said knob has an upwardly extending pointer portion 26 which cooperates with a curved dial plate 27 hearing graduations and indicia indicative of different stitch lengths in the forward and reverse directions. The knob 25 may be formed of any suitable material either metal or plastic, but preferably the latter, and its inner end including the indicating portion 26 may be reenforced by a metal plate 28 fixed to the knob in any desired way.

A sleeve 29 having at one end an annular flange 30 surrounds the shaft 13, spring 24 and sleeve 22 and is secured to the outer side of the wall 12 by threaded securing members 31 passing through the flange 30 and screwed into threaded openings in the wall 12. The sleeve 29 has at its outer end and on its upper portion a reentrant V-shaped notch with the opposite inclined walls 32 thereof being symmetrical and terminating at their outer ends in parallel wall portions. The upper end 21!) of the pin 21 carried by the sleeve 22 extends into this reentrant notch and said upper end 21b of the pin is normally held against one of the inclined walls 32 by the action of the torsional spring 19, i. e., the inclined wall 32, which may be designated the forward wall. The inclined walls 32 maybe termed camming surfaces, as will now be pointed out in describing the operation of the mechanism. Assuming stitching mechanism of the sewingtmachine will thcn be:

adjusted to zero stitch length; Now'assuming that the operator turns the adjustingor stitch lengthiselecting disla 23 so thatit-will screwoutwardly onithe shaft 13, it will be understood that the sleeve 22.will follow the disk 23 under the action of the spring 24iand'the upper' end 21b of the'pin 21 willmove outwardly-along. the forward camming surface. 32 and will beheld in contactwith said surface by the spring-19e The movementof the upper: end12 1b oflthe pin 21 along the forward tcamming: surface 321and the action-of the spring 19in holdingsaidfupper end in contaetwithtthe surface results in the spring 19fimparting:aturningmovement toitheshaft 13and' the extent of this turning move ment is-iindicated; to the operator by the indicating por tion 26 of :the knob 25 which'lattertis fixed to the shaft' 13. When theldisk 23 has. been turned;.fr:instance, antamount such that the shaft l3zhas turnediunder the action of the spring 191 to adjust the stitching mechanism to astitch length: represented byithegraduation. bearings-the numeral 2 of .the dial 27 'and'inthe-forward direction,- the operator:

will know he has selected this length stitch or whatever" length stiteh' he may-desire as IhfiCfiSGHlEIYbC; The parallel wall portions at the outer ends of theiwall 32provide a safetymarginso the pin =endi21b: willinot:be moved in 0 advertently ,out of engagement .with ithe wall 32 iby-over turning the disk 23.

The operator can .now proceed, to sew in the forward direction at the stitch length thus {selected and whenthe forward stitching until it 'is :inthe corresponding?stitch length position on the reverseside' ofithe dial 27'." This turning movement of theknob 25' moves=the upper end 21b of the pin from theforward cammingi sunface 32"of the sleeve 29 directly across the reentrant notch to the-reverse camming surface 32.asindicated. bydotted lines in' Fig. 4; it being understoodthat thevsleeve 22, due to its:

splined connection with the shaft 13,, turnsawith the latter. Then when the operator has taken the requisitei num ber of stitches of the same length on the opposite direc-' tion, all that need be'done is to releasetherknob 25; whereupon the spring 19 :rotates the shaft 13'and moves the'upper end 21b ,of the pin 21 straight across the-reentrant notch from the reversecamming surface 32- to its former position in engagement with theforwardcam' ming surface 32 which effects adjustment .oflthe-sewing' mechanism for forward stitching with theestitchz lengthpreviously selected.

In some sewing mechanisms themeans for adjusting:

the same to provide for different.lengthtandrdirection:of stitches isso constructed that, for. any particular stitch' length a different adjusting movement is required for:

forward stitching from that required for reverse stitching.

When the sewing machine has a type of mechanismas just" referred to, then the camming surfaces 32 will not be symmetrical andidentical, but the forward cammingsurface-i 32a of Fig; 5 will be disposedat a diflerentangle' fromthereverse camming surface 32b, but otherwise the sleeve 29 of. Fig.5 will be the same as the sleeve 29 previously de-' scribed.-

Although preferred embodiments of the inventionhave been illustrated and deseribed,it willibe:understoodrthat the invention is susceptible of. various -modificationsaand adaptations within the scope :of the appendedrclaims.

Having thus described;my-invention,.-I claim: i

1. In a sewing machineof the type having abed-platesupporting thereon an upwardly extending head and proded below the bedplate: with a stitch formingand tagulating mechanism including adjustable means to vary the stitch length and direction, a rockable shaft carried by the head and extending outwardly of the front side thereof, a member within the head secured to said shaft for connecting it with the adjusting means of the stitch forming and regulating mechanism, a cam member fixedly secured to the head and providedwith oppositely disposed forward andireversedcammingsurfaces extending in a direction substantially axially of said shaft, cam follower means coaxially carried by and rockable with-said shaft and normally cooperating with the forward cammingsurface and adjustable axially of said shaft and along said forward camming" surface to provide forditferent stitch lengths in the forward direction, spring means acting on said shaft to rock the same in one direction and hold said cam follower means in engagement with said forward camming surface, and manually operated means mounted on said shaft outwardlyofthe front side of tlt'e head for rocking said. shaftinthe oppositedirection to engage said follower with the other or reverse-camming surface to obtain the samelength stitch but in the-opposite direction.

2. In a sewing machine asdefined in claim 1 and whereinthere is provided meansiadjustable-on said' shaft for adjusting said :camfollower means axially ofsaid shaft'tofollower means includes an element locatedin said notch and normally held by said spring means in contactwith said angularly disposed forward camming surface.

4. In asewing machineasdefi'ned in claim- 3 and whereinsaid cam 'follower' means is 'a sleeve splined to said shaft for axial movement'thereon-and rocking movement therewith land has a pin projecti ng radially from its cit cumferen'ce'and located in'said notch of said'cammem her. and engageable normally with the-angularly disposed forward camming surface thereof.

5. In a sewing machine as definedin claim 4'and wherein-the adjustingmeansfor said'camfollower'means is a diskthreaded'onsaid shaft forrotation thereon, while the splined sleeve ofsaid 'cam *followermeans is'held in contact with said disk by a spring'meansactingthereon.

6.- In a sewing machine of the type'havinga -bed'plate supporting on its upper side a head and'provided below the bedplate with a sewing mechanism including means adjustable tovary the stitch length and direction, a shaft rockably mounted in said head and extendinggoutwardly of thefront side thereof, a member within the head so cured to said shaft forconnecting it"withthe"adjustiug means of the-sewing mechanism, a cam'sleeve'fixedly secured to the head concentrically-with"saidshaft but radially'spaced therefrom and provided with a reentrant notch" having angularly disposed *sidesconstituting forward and reverse camming surfaces, a cam follower carryingsleeve slidable on-said shaft and mounting aipin 'havingat' its inner end a portion extending into an'axial slot .in said shaft and at its outer end a cam follower portion located in said reentrant notch, a' disk threaded on said shaft outwardly of the head, a spring acting on said cam follower carrying sleeve and holding it in contactwith said disk whereby rotation of said disk effects axial movement of said sleeve and adjusting movement ofsaidlcam fol lower portion of said pin in said notch, an indicating knob secured on said shaft outwardlyjof said disk and provided with an indicating pointer, a dial on said head cooperating with said pointer, and torsional spring means actingon' said shaft to rock it in onedirectidn and 'maintain said cam follower portion' ofsaid pinin'contactwith said for" ward camming surface, whereforesaid" indicating 'knob" can be manually -turned'to rock said-shaf-t in the op 5 posite direction against the action of said torsional spring means and move said cam follower portion of said pin across said notch to engage the reverse camming surface thereof to obtain the same stitch length in the reverse direction.

References Cited in the file of this patent UNITED STATES PATENTS 2,420,480 Ivandick May 13, 1947 Austlid Oct. 10, 1950 Abos et al. July 24, 1951 FOREIGN PATENTS Great Britain 1906 Great Britain July 4, 1929 France Apr. 20, 1936 Switzerland May 1, 1953 

